96 results about "Background fluorescence" patented technology

The invention discloses an automatic focusing method and system of a cell slide scanner, and relates to the related field of optical equipment focusing technology.The method comprises the steps that a slide is previewed and scanned, a multi-mode preview image and physical height sensing data are synchronously collected and preprocessed, and then the pre-processed image is obtained; the multi-modal preview image and the corresponding height data are input into a pre-training focus prediction model, a focusing strategy graph aligned with a slide coordinate space is output, and the graph comprises the predicted optimal focus offset, the focusing function recommendation identifier, the focus verification confidence coefficient and the search radius of each view point; according to the focusing strategy graph, a final focus is determined through feedforward positioning, limited verification and conditional adjustment, a scanner objective table is controlled to carry out formal scanning at the final focus position, and a complete scanning image of the cell slide is collected. The problems that a traditional focusing method is long in time consumption and poor in adaptability to complex samples with low contrast, high background fluorescence and scratch pollution are solved, and the adaptive capacity of the focusing process is improved.

The invention provides a multi-focus excitation confocal fluorescence microscopic imaging flow cytometry screening method. The method is characterized in that a laser beam generates three laser beams through a spatial light modulator, and the three laser beams are coherently superposed in a focal plane of a microscope objective to generate a two-dimensional optical lattice light field. And after the other laser beam is shaped by the cylindrical lens, linear laser optical tweezers are realized through the microscope objective, cells to be detected in an imaging detection area of the micro-flow chip are captured, and accurate active optical control on the rotation angle of the cells to be detected is realized. In a cell rotation process, a two-dimensional optical lattice light field rapidly scans in a focal plane at different angles, and a fluorophore in the cell is excited to generate a fluorescence signal. The confocal pinhole array installed at the position conjugate with the focal plane eliminates background fluorescence, a high-spatial-resolution fluorescence image of a three-dimensional structure in the cell is obtained, and cell screening is achieved. The method provided by the invention has the characteristics of high detection rate, high accuracy and the like, and has wide application prospects in the research fields of biology, medicine and life science.

The invention belongs to the technical field of talc, and provides a method for detecting fluorescent substances in talc raw ore, which comprises the following steps: S1, carrying out ball milling on the talc raw ore in a ball mill, sieving to obtain sieved powder, and adding deionized water into the sieved powder to obtain slurry; s2, adding the slurry into the mixture to enable the pH value of the slurry to be 5, stirring, and standing in a water bath for 2-3 hours to obtain a first precipitate; s3, adding a thiourea-ascorbic acid solution into the first precipitate to obtain a second precipitate; and S4, carrying out secondary ball milling on the second precipitate, and spreading the second precipitate in an enamel plate to detect whether the talc raw ore contains the fluorescent substances or not. The hydrochloric acid can dissolve quartz and mica to avoid generation of background fluorescence or quenching effect, and the nonionic surfactant polyethylene glycol can be adsorbed on the surface of the mineral to reduce interfacial tension, so that the hydrochloric acid is easier to infiltrate tiny pores, the pit defect caused by local over-corrosion is reduced, the pickling uniformity is improved, and the detection sensitivity is improved.

The application relates to establishment and application of an isobutyraldehyde biosensor and belongs to the technical field of bioengineering. yqhD The RFP report system responding to isobutyraldehyde is established, the yqhC gene is rationally designed, a mutant library is constructed through random mutation by using error-prone PCR, isobutyraldehyde is used as a substrate, and through screening of response concentrations and response thresholds, a YqhC mutant without background fluorescence response, with a wider substrate detection range (0-5 g / L) and higher response intensity (24 times) is obtained, and the YqhC mutant is named YqhCm9. The isobutyraldehyde response element (YqhCm9) and the fluorescent protein report element (RFP) are used to construct a high-efficiency and specific isobutyraldehyde biosensor, real-time monitoring of an isobutyraldehyde production process and screening of an isobutyraldehyde production strain can be carried out.

The application discloses an up-conversion fluorescent probe, an isoniazid detection method and a portable isoniazid detection sensor and belongs to the field of biological detection. The up-conversion fluorescent probe is composed of lanthanide-doped core-shell structure up-conversion nanoparticles subjected to acid pickling treatment and p-dimethylaminobenzaldehyde, wherein the core particle diameter of the up-conversion nanoparticles is 25.85-28.85 nm, and the shell layer thickness is 0.98-1.38 nm. The lanthanide-doped core-shell structure up-conversion nanoparticles are used as an energy donor, and the p-dimethylaminobenzaldehyde is used as a specific recognition molecule, and ratio-type fluorescence detection is realized through an inner filter effect. Isoniazid reacts with DMAAB to generate a Schiff base, which causes fluorescence quenching at 475 nm and no change in 655 nm fluorescence, so that the fluorescence color changes from blue to red. Due to the near-infrared excitation characteristics of the up-conversion nanoparticles, the up-conversion nanoparticles are not easily disturbed by background fluorescence, so that rapid quantitative detection of isoniazid in whole blood is realized, and the detection limit is as low as 2.4 μm. The application is simple in operation, strong in anti-interference and suitable for clinical individualized drug monitoring.

The invention provides an intelligent tongue picture feature identification method and system, relates to the technical field of biomedical detection, and aims to avoid confusion of subsequent signal processing caused by environmental noise by accurately identifying and eliminating ambient light interference with fixed frequency through fast Fourier transform analysis after a pre-processed original composite light signal is obtained. When the target lingual surface area shifts to cause dynamic change of the background fluorescence signal, the preset adaptive filtering algorithm can accurately identify and reject the changed background fluorescence digital signal values of the tongue picture in real time. The step-by-step and self-adaptive processing strategy ensures that the removal of ambient light interference and the correction of the background fluorescence signal are mutually independent and do not interfere with each other, thereby avoiding the generation of internal processing conflicts and calculation artifacts described in the background technology, and obtaining highly pure and accurate tongue picture fluorescence digital signals. The accuracy and reliability of tongue picture feature identification are remarkably improved, and a more reliable data basis is provided for oral health detection.

The present application relates to a kind of high efficiency response vanillin biosensor, belong to the field of bioengineering technology.The present application utilizes aldehyde response transcription factor YqhC of escherichia coli ( Escherichia coli ) origin and the promoter element of the regulated P yqhD Establishment of RFP report system of vanillin response, to yqhC Gene semi-rational design is carried out, and mutant library is constructed by saturation mutation, with vanillin as substrate, by screening response concentration and response threshold, obtain no background fluorescence response, with wider substrate detection range (0-10 mM), and response intensity is higher (167 times) YqhC mutant, it is named YqhC-V18.Further, the biosensor containing vanillin response element (YqhC-V18) and fluorescent protein report element (RFP) is obtained, which can be applied to detect vanillin-containing sample, or screen vanillin production strain, or regulate vanillin production process.

The invention discloses a self-adaptive fluorescent dark background removal method, device and equipment and a medium, and relates to the technical field of image processing, and the method comprises the steps: obtaining a mask of a fluorescent image for a target sample; performing large-size low-pass filtering smoothing processing on the fluorescence image to obtain a background layer image; subtracting the background layer image from the fluorescence image to obtain a weak background fluorescence image; based on the mask, extracting a non-mask region from the weak background fluorescence image as a background noise region image; performing image filling on a mask region in the background noise region image to obtain a pure background image; smoothing the pure background image; and subtracting the pure background image after smooth processing from the weak background fluorescence image to obtain a corrected target image. The method does not need to pre-store or pre-collect background data, can adaptively estimate and deduct complex backgrounds including internal noise of samples, remarkably improves the signal-to-noise ratio and quantitative accuracy, and solves the problems that a traditional method is tedious in operation, poor in adaptability and incomplete in denoising.

The invention discloses a near-zero background fluorescence sensor based on polydopamine functionalized MXene as well as a preparation method and application of the near-zero background fluorescence sensor, and belongs to the technical field of universal biosensing. The sensor comprises a polydopamine functionalized MXene material and a quantum dot-aptamer fluorescent probe which is accurately coupled by click chemistry in a ratio of 1: 1. The detection method is characterized in that a target object is utilized to induce the probe to desorb from the surface of a material, and a supernatant containing the free probe is physically separated from a material precipitate through centrifugal separation, so that background fluorescence interference is almost completely eliminated. According to the invention, ultra-sensitive detection of aflatoxin B1 is realized, and the detection limit of AFB1 in complex matrixes such as corn flour is as low as 0.27 mu g / kg. All components of the platform can be modularly and independently stored for a long time, the platform can be directly applied to detection of various micromolecular mycotoxins without optimization by replacing aptamers, and the platform has high sensitivity, high stability and high universality.

The invention belongs to the technical field of chrysin detection, and particularly relates to a dual-emission fluorescent molecularly imprinted polymer as well as a preparation method and application thereof. The method comprises the following steps: preparing carbon dots with different emission wavelengths; carrying out amination modification on the carbon dots; and preparing the dual-emission fluorescent molecularly imprinted polymer. The method also comprises the following steps: respectively adding the dual-emission fluorescent molecularly imprinted polymer into chrysin solutions with different known concentrations, carrying out fluorescence quenching reaction, and establishing a standard curve according to the linear relationship between the detected fluorescence intensity and the corresponding concentration of the chrysin solution; adding the dual-emission fluorescent molecularly imprinted polymer into a solution of a to-be-detected product, and carrying out fluorescence quenching reaction to obtain fluorescence intensity; and calculating the concentration of chrysin in the solution to be detected according to the standard curve. The preparation method is used for solving the technical problems that in the prior art, a single-emission fluorescent molecularly imprinted polymer has defects in the aspects of sensitivity, background fluorescence interference resistance in a complex environment and the like in the detection process.

The application discloses a double-line ratio fluorescent competitive immunochromatographic detection device and a preparation method and application thereof, and relates to the technical field of immunochromatographic detection.The detection device comprises a double-specificity recognition unit mixed-labeled quenched fluorescent probe, a background fluorescent material and a solid phase substrate, the solid phase substrate is provided with a T line on which a target object binding ligand is immobilized and a C line on which a quality control ligand is immobilized; and the application also provides application of the detection device in detection of exogenous harmful substances.The application solves the technical problem of low detection sensitivity of the existing method, and adjusts the binding amount of the probe on the T line and the C line through an immune competition reaction, adjusts the quenching degree of the background fluorescence based on an internal filter effect, takes (T line quenched fluorescent signal / background fluorescent signal) / (C line quenched fluorescent signal / background fluorescent signal) as a quantitative signal, and takes the C line to participate in ratio calculation to improve the detection sensitivity, so that the application is suitable for high-sensitivity qualitative and quantitative detection of small molecule compounds and the detection sensitivity is improved.

An analytical method of and system for monitoring cell status whereby excitation energy is focused to an excitation cytometry volume in a cell sample to fluoresce first and second fluorophores of a cell. Fluorescence signals from the first and second fluorescing cell fluorophores are directed to a detection subsystem. A first peak in fluorescence intensity for the first fluorophore is detected as is a second peak in fluorescence intensity for the second fluorophore. The fluorescence signals are processed to identify when the first and second peaks occur substantially simultaneously indicating the presence of a cell at the excitation cytometry volume instead of background fluorescence and in response, the cellular status of the cell is measured using the intensity of the levels of the first and second peaks.

The invention relates to the technical field of biological medicine, in particular to a TREM-1 targeted fluorescent molecular probe as well as a preparation method and application thereof, and discloses a fluorescent molecular probe named as' TREM-1 targeted fluorescent molecular probe as well as a preparation method and application thereof '. The invention aims to solve the problems of large molecular weight, poor pharmacokinetic performance, limited tissue penetration, high imaging background and poor imaging timeliness of the existing antibody fluorescent probe. The probe comprises a TREM-1 targeting module (TDM), a near-infrared fluorescence reporter group, a dark quenching group and a conformational sensitive connecting arm (CSL). The fluorescence of the probe is quenched before the probe is combined with TREM-1, and after the probe is combined with a target spot, TDM specific binding induces CSL conformation rearrangement, so that a reporter group and a quenching group are spatially separated, fluorescence resonance energy transfer (FRET) is relieved, and fluorescence activation is realized. According to the invention, rapid, high-contrast and low-background fluorescence imaging of atherosclerotic plaques is realized, and the probe is small in molecular size, strong in tissue penetrability and rapid in-vivo clearing.

The invention discloses an enzyme-activated fluorescent molecular precursor as well as a preparation method and application thereof. The enzyme-activated fluorescent molecular precursor has a chemical structure as shown in a formula I which is described in the specification. The invention develops an enzyme-activated fluorescent molecular precursor which can be used for real-time imaging of tumors by targeting exogenous enzyme to the tumors and specifically activating a probe at the tumors; according to the invention, the exogenous enzyme is introduced as an activation trigger, and normal cells do not have the exogenous enzyme, so that the problem of co-expression of the endogenous enzyme in non-tumor tissues can be avoided, background fluorescence signals can be reduced to the greatest extent, and the imaging specificity and accuracy are remarkably improved.

The invention relates to the technical field of food hazard factor detection, in particular to a food hazard factor detection method and system based on biomimetic hydrolase catalytic fluorescence generation. Comprising the following steps: S1, obtaining a turbidity characteristic value, background fluorescence intensity and a fluorescence quenching coefficient of a to-be-detected sample solution; s2, based on the turbidity characteristic value and the fluorescence quenching coefficient, calculating to obtain a robustness index; s3, according to a comparison result of the robustness index and a preset qualified threshold value, through a preset closed-loop feedback control logic, determining a working gain used for total fluorescence intensity signal acquisition; s4, performing dynamic signal correction processing including gain normalization to obtain a normalized apparent fluorescence signal; s5, based on the normalized apparent fluorescence signal, calculating to obtain an apparent catalytic rate; and S6, determining the concentration of the target hazard factor according to the apparent catalytic rate, the turbidity characteristic value and the fluorescence quenching coefficient. According to the method, the accuracy and the reliability of detecting the target hazard factors in the complex matrix are remarkably improved.

The invention discloses a near-infrared photosensitizer for specifically recognizing fibroblast activation protease (FAP-alpha) as well as a preparation method and application of the near-infrared photosensitizer. A cyanine derivative is used as a fluorescent parent nucleus (ICyOH) of the photosensitizer, the fluorescence of the photosensitizer can be almost completely masked by modifying the photosensitizer, and after the photosensitizer reacts with FAP-alpha for 60 minutes, the fluorescence intensity is rapidly enhanced, so that high sensitivity, good selectivity and anti-interference performance are shown. The ZGP-LL-ICy is a photosensitizer with a cyanine structure, FAP-alpha fluorescence enhancement and high selectivity to FAP-alpha, the reagent shows high selective response to FAP-alpha enzyme, active ICyOH molecules with near-infrared fluorescence are released under the action of enzymolysis, and tumor fluorescence imaging of deep tissue penetration is achieved. Meanwhile, the activated ICyOH can generate cytotoxic active oxygen under the illumination condition, and photodynamic therapy on pancreatic cancer is achieved. The reagent has the advantages of low background fluorescence, deep tissue penetration, diagnosis and treatment integration and the like, and has important application value in the fields of early diagnosis and precise treatment of pancreatic cancer.

The invention relates to the technical field of high polymer materials, in particular to a laser high-sensitivity film for a low-fluorescence PC identification card and a preparation method thereof.The preparation method comprises the steps that 10 parts of PC resin is ground into 200-mesh powder according to the proportion, the powder, a triazine light stabilizer, a nickel complex and a laser photosensitizer are stirred at a high speed for 10 min (400 rpm), then the mixture is cooled to 60 DEG C or below at a low speed, and the mixture is discharged to a discharging bin to obtain a mixture; carrying out twin-screw granulation to obtain high-concentration light stabilizer master batch; drying the master batch at 80 DEG C for 4 hours, mixing the master batch with 90 parts of PC resin, and preparing a PC film through an extrusion casting machine; finally, the PC film is cooled and shaped through equipment such as a melt filter, and the uniformly-dispersed low-fluorescence PC film is obtained, so that the problem that a film material in the prior art is difficult to maintain original excellent mechanical and optical properties of polycarbonate is solved, background fluorescence of the material under the ultraviolet light condition can be effectively inhibited, and the low-fluorescence PC film is prepared. And the technical problem of color interference or transparency reduction is not introduced.

The near-infrared window of fluorescent heptamethine cyanine dyes greatly facilitates biological imaging because there is deep penetration of the light and negligible background fluorescence. But dye instability, aggregation, and poor pharmacokinetics are current drawbacks that limit performance and the scope of possible applications. All these limitations are simultaneously overcome with a new molecular design strategy that produces a charge balanced and sterically shielded fluorochrome. The key design feature is a meso-Aryl group that simultaneously projects two shielding arms directly over each face of a linear heptamethine polyene. Cell and mouse imaging experiments compared a shielded heptamethine cyanine dye (and several peptide and antibody bioconjugates) to benchmark heptamethine dyes and found that the shielded systems possess an unsurpassed combination of photophysical, physiochemical and biodistribution properties that greatly enhance bioimaging performance.

The application discloses a beta-galactosidase near-infrared fluorescent probe with a large stokes shift and a preparation method and application thereof. The structure of CPD-gal is shown in formula I. When a 580nm excitation wavelength is used for excitation, CPD-gal has weak fluorescence at 713nm, but can selectively undergo a fluorescence opening reaction with beta-gal. With the increase of the concentration of beta-gal, the fluorescence intensity at 713nm is gradually enhanced, and other interfering ions and species will not interfere with the detection of beta-gal by CPD-gal. Since the emission wavelength is in the near-infrared region and a large stokes shift is generated, the system background fluorescence interference is greatly reduced, and the sensitivity of the detection of beta-gal is improved. Therefore, CPD-gal is suitable for the fluorescence detection of beta-gal with high selectivity and high sensitivity. The probe is successfully applied to the fluorescence imaging of endogenous beta-gal in HeLa cells and SK-OV-3 cells.

The invention provides an immunochromatography detection result reading method and device based on solid quantum enhancement, and relates to the technical field of immunochromatography detection. The immunochromatography detection result reading method comprises the following steps: emitting exciting light to a standard substance to excite the standard substance to generate a fluorescence signal for detection; microwaves are output to a standard substance, so that the standard substance generates spin resonance, and the intensity change of a fluorescence signal is caused; collecting the fluorescence signal after intensity change to obtain an optical detection magnetic resonance ODMR reference spectral line; determining a corresponding microwave calibration frequency according to the optical detection magnetic resonance ODMR reference spectral line; exciting light and microwaves which are calibrated according to the microwave calibration frequency and are subjected to amplitude or frequency modulation are emitted to a tested sample; and respectively detecting the fluorescence intensity variation of the quality control line and the detection line to obtain an immunochromatography detection result of the detected sample. The microwave frequency is calibrated by using the standard substance, the interference of background fluorescence is effectively shielded, and the detection sensitivity and accuracy are improved.

The invention discloses a fluorescent probe for detecting arginine aminopeptidase as well as a preparation method and application of the fluorescent probe, and belongs to the technical field of biological medicines. The fluorescent probe (DDAR) provided by the invention can be hydrolyzed by arginine aminopeptidase (RAP) at high selectivity to generate a hydrolysate of which the fluorescence attribute is remarkably changed, so that high-specificity detection can be realized through a fluorescence detector. Moreover, the probe reaction system can be used for quantitatively evaluating the activity and function of the arginine aminopeptidase in an intestinal microorganism sample, and can be used for screening an arginine aminopeptidase inhibitor. The DDAR provided by the invention has long fluorescence emission wavelength, can well weaken interference of biological background fluorescence, and has high sensitivity. The fluorescent probe for detecting arginine aminopeptidase provided by the invention can be prepared through a simple chemical synthesis process, the preparation process is simple and easy to implement, the detection cost of a fluorescent method is low, and the fluorescent probe has a very good application value.

This invention discloses a viscosity-fluorescent probe based on indole derivatives, its preparation method, and its application, belonging to the field of fluorescent materials and biodetection technology. The molecular formula of the probe in this invention is C1. 34 H 29 N2 + ·ClO4 ‑ The structural formula is as follows: The indole derivative-based fluorescent probe for viscosity detection designed in this invention has a short synthesis path and a simple post-processing procedure. It exhibits strong response specificity, high sensitivity, and good selectivity, with a large Stokes shift and fluorescence enhancement factor, reducing background fluorescence interference during imaging and enabling rapid, visualized, and selective detection of viscosity.

The invention belongs to the technical field of fluorescence detection, and particularly relates to a ratio-dependent up-conversion fluorescence nanoprobe for veterinary drug detection and a preparation method and application of the ratio-dependent up-conversion fluorescence nanoprobe. The invention provides a ratio type up-conversion fluorescent nanoprobe for veterinary drug detection. The ratio type up-conversion fluorescent nanoprobe comprises a core nanoparticle NaGdF4: Yb / Tm, an inner layer shell NaYbF4, a middle layer shell NaGdF4: Yb / Er and an outer layer shell NaYF4 from inside to outside, after the fluorescent probe is incubated with furaltadone and malachite green, the fluorescence intensity is quenched, the selectivity is good, and the fluorescent probe can be used for detecting furaltadone and malachite green; furthermore, as a ratio-type up-conversion fluorescent nanoprobe, the fluorescent nanoprobe can be excited by low-energy near-infrared light, does not cause light damage, has higher biological tissue penetration depth, no background fluorescence interference and higher signal-to-noise ratio, and is a fluorescence detection method for veterinary drug residues with excellent reliability; therefore, the technical problem of low reliability of fluorescence detection of veterinary drug residues in the prior art is solved.

A fluorescent dye, as well as a preparation method and uses thereof, wherein the fluorescent dye is sensitive and specific to viscosity and has low background fluorescence; it can also be used as a fluorescent activated and lighted probe used for fluorescent labeling, quantification or monitoring of protein, enzymes or nucleic acid.

The invention provides a homogeneous immune FRET (Fluorescence Resonance Energy Transfer) analysis method and application of alginate, and belongs to the technical field of analytical chemistry and biosensing. The alginate fluorescent probe is prepared by respectively marking FRET donors and receptors on alginate by utilizing the high-specific recognition characteristic of a catalytic inactivated alginate lyase or carbohydrate binding module thereof on the alginate, and the probe is randomly combined on alginate molecules with a linear repetitive skeleton in a novel'sugar-coated haw 'structure. At an appropriate probe: alginate binding ratio, FRET donors and receptors are close to each other and generate FRET signals. The lanthanide complex is used as a fluorescence donor, and short-life background fluorescence interference in a biological sample is effectively filtered out by utilizing the long-life luminescence characteristic of the lanthanide complex. Compared with a conventional polysaccharide analysis method which usually needs a complex pretreatment process and relatively long detection time, the method disclosed by the invention can realize high-sensitivity, high-specificity, rapid and homogeneous immunofluorescence quantitative detection of algal polysaccharides in a biological sample.

This invention belongs to the field of environmental biodetection technology and discloses a design method for a highly sensitive microbial sensor for the detection of heavy metal copper. The invention introduces the cusR gene to form a positive feedback circuit, combined with a repL signal amplification module to further improve the fluorescence output intensity of the whole-cell biosensor; introduces the cusS gene to reduce the background fluorescence of the sensor, improving sensitivity and optimizing selectivity for copper ions; and uses a double knockout strain to lower the detection limit. Optimizing cell culture conditions during the testing process further significantly improves the sensor sensitivity. The finally constructed positive feedback whole-cell biosensor Cu26 based on the cusRS two-component system, under the newly invented culture and detection procedure, detects Cu26... 2+ The detection limit was reduced to 0.1 μM, and the induction coefficient at 1 μM reached ~100 times, significantly improving both sensitivity and selectivity, while greatly shortening the cell culture time during detection.

The invention belongs to the technical field of biology, and particularly relates to optimization of an intracellular nucleic acid labeling technology, and a composition for reducing a nucleic acid labeling background signal comprises a first expression construct; and a second expression construct. The composition has the advantages of being good in effect of reducing non-specific background fluorescence signals, high in controllability, wide in compatibility, easy and convenient to operate, small in influence on cell viability and the like, corresponding recruitment modules are induced to conduct specific binding through exogenously added chemical molecules, positioning signal elements are ingeniously configured, and the application range of the composition is widened. Therefore, directional migration (from intra-nucleus output to cytoplasm or from cytoplasm input to intra-nucleus) of non-specific background fluorescence signals is realized, the imaging quality of living cell nucleic acid labeling is remarkably improved, and the application prospect is wide.

This invention discloses a multi-stimulus-responsive upconversion luminescent nanocrystalline magnetic microsphere and its preparation method, belonging to the field of biomedical polymer materials and nanobiotechnology. The microsphere's main body is a porous copolymer matrix, encapsulating a core of magnetite (Fe3O4) magnetic nanocrystals. Rare-earth-doped fluoride upconversion luminescent nanocrystals are coupled to the surface and pores. The copolymer side chains of the microsphere incorporate azide groups, acidic stimulus-responsive groups, and photostimulation-responsive groups, constructing an independent and non-interfering triple orthogonal logic gating system on the surface. The preparation method includes preparing an oil phase containing copolymers, magnetic nanoparticles, and a volatile porogen; pre-emulsifying and homogenizing the oil phase in an acidic aqueous phase using an SPG membrane; inducing phase separation by controlled solvent evaporation to form porous microspheres; and finally coupling the upconversion nanocrystals via a click chemistry reaction. The magnetic microspheres of this invention eliminate background fluorescence interference from complex samples from a physical perspective. Their porous structure endows the microspheres with excellent quasi-levitation properties and magnetic responsiveness, effectively solving problems such as single surface function and signal crosstalk of microspheres. They are suitable for in vitro clinical diagnosis and complex analysis of multiple targets.

This invention belongs to the fields of biomedicine and fluorescent probe technology, and relates to a biheaded functional molecule and its application in the preparation of products for imaging cell tailpods or migration bodies. The biheaded functional molecule has the chemical structure shown in Formula I; wherein R is a hydrophilic positive ionic fluorescent group, X is methylene or O, Y is methylene or carbonyl, and n is 1~3. The biheaded functional molecule provided by this invention can achieve long-term cell membrane anchoring and can dynamically track the migration body formation process with low phototoxicity, low background fluorescence, high photostability, and high brightness.